at length的近义词有：at last, at length, eventually, finally, in the end, lastly。下面这些词或词组均含有"最后，终于"的含义：at last ：多指经主观努力，克服各种困难后才终于达到目的。at length ：强调经历一段长时间后终于完成，侧重在时间部分。eventually ：侧重于动作或行为的结果。finally ：常与at last换用，都可用于对往事的描述，但...
The guy just loves to yap, and will do so at length.那家伙就爱胡扯，而且一说起来就没完没了。They spoke at length, reviewing the entire incident.他们把事情的整个经过详尽地复述了一遍。He talked at length about his work and his family.他详谈他的工作和家庭....